|STRSEP(3)||FreeBSD Library Functions Manual||STRSEP(3)|
NAMEstrsep — separate strings
LIBRARYStandard C Library (libc, -lc)
SYNOPSIS#include < string.h>
strsep( char **stringp, const char *delim);
DESCRIPTIONThe strsep() function locates, in the string referenced by *stringp, the first occurrence of any character in the string delim (or the terminating ‘
\0’ character) and replaces it with a ‘
\0’. The location of the next character after the delimiter character (or NULL, if the end of the string was reached) is stored in *stringp. The original value of *stringp is returned.
An “empty” field (i.e., a character in the string delim occurs as the first character of *stringp) can be detected by comparing the location referenced by the returned pointer to ‘
If *stringp is initially NULL, strsep() returns NULL.
EXAMPLESThe following uses strsep() to parse a string, and prints each token in separate line:
char *token, *string, *tofree; tofree = string = strdup("abc,def,ghi"); assert(string != NULL); while ((token = strsep(&string, ",")) != NULL) printf("%s\n", token); free(tofree);
The following uses strsep() to parse a string, containing tokens delimited by white space, into an argument vector:
char **ap, *argv, *inputstring; for (ap = argv; (*ap = strsep(&inputstring, "\t")) != NULL;) if (**ap != '\0') if (++ap >= &argv) break;
HISTORYThe strsep() function is intended as a replacement for the strtok() function. While the strtok() function should be preferred for portability reasons (it conforms to ISO/IEC 9899:1990 (“ISO C90”)) it is unable to handle empty fields, i.e., detect fields delimited by two adjacent delimiter characters, or to be used for more than a single string at a time. The strsep() function first appeared in 4.4BSD.
|December 5, 2008||FreeBSD|